Observers with small, but finite, peculiar velocities relative to the Hubble flow can measure a negative deceleration parameter, although the universe may be actually decelerating. The effect is local but it can affect large enough scales to give the impression that the whole universe had recently entered an accelerated phase. We outline the key features of the accelerating mechanism and discus...

The dependence of the lateral distribution of Cherenkov light in simulated extensive air showers to the energy and the mass of the primary cosmic rays has been studied. It has been shown that a previous claim about mass independent proportionality of shower energy to the total Cherenkov photon number is not valid in energies below EEAS ~ 1014 eV. We have found that the core distance of the so c...

We extend the formalism of the relativistic thermal Sunyaev-Zel’dovich effect to the system moving with a velocity ~ β ≡ ~v/c with respect to the cosmic microwave background radiation. In the present formalism, the kinematic Sunyaev-Zel’dovich effect for the cluster of galaxies with a peculiar velocity ~ β is derived in a straightforward manner by the Lorentz boost of the generalized Kompaneets...

We discuss the signature of the scale of short distance physics in the Cosmic Microwave Background. In addition to effects which depend on the ratio of Hubble scale H during inflation to the energy scale M of the short distance physics, there can be effects which depend on φ̇/M where φ is the classical background of the inflaton field. Therefore, the imprints of short distance physics on the spe...

After a short history of the Λ-term it is explained why the (effective) cosmological constant is expected to obtain contributions from short-distance-physics, corresponding to an energy scale of at least 100 GeV. The actual tiny value of the cosmological constant in any natural scale of units represents, therefore, one of the deepest mysteries of present day fundamental physics. We also briefly...

Based on concepts drawn from the ekpyrotic scenario and M-theory, we elaborate our recent proposal of a cyclic model of the Universe. In this model, the Universe undergoes an endless sequence of cosmic epochs which begin with the Universe expanding from a ‘big bang’ and end with the Universe contracting to a ‘big crunch.’ Matching from ‘big crunch’ to ‘big bang’ is performed according to the pr...

In thermal leptogenesis, the cosmic matter-antimatter asymmetry is produced by CP violation in the decays N → l + Φ of heavy right-handed Majorana neutrinos N into ordinary leptons l and Higgs particles Φ. If some charged-lepton Yukawa couplings are in equilibrium during the leptogenesis epoch, the l interactions with the background medium are flavor sensitive and the coherence of their flavor ...

We extend the formalism of the relativistic thermal and kinematical SunyaevZeldovich effects to the observer’s system (the Solar System) moving with a velocity ~ βS ≡ ~vS/c with respect to the cosmic microwave background radiation. We confirm the results recently obtained by Chluba, Huetsi, and Sunyaev in the lowest order of the observer’s velocity βS. We give a more general analytic expression...

In this Letter we use the unprecedented spatial resolution of the Chandra X-Ray Observatory to carry out, for the first time, a measurement of the post-shock electron temperature and proper motion of a young SNR, specifically to address questions about the post-shock partition of energy among electrons, ions, and cosmic rays. The expansion rate, 0.100% ± 0.025%yr, and inferred age, ∼1000 yr, of...